After you've copied wordpress folder/files to your localhost directory, create the wordpress database like you normally would and once you've done that, follow these steps carefully:
###Step 1: CREATE SITE ALIAS
If you're not using MAMP Pro or any fancy webserver, you'll have to create this manually by editing your host file, here's how:
open your terminal and type these commands in:
sudo vi /etc/hosts"
# add the following lines:
127.0.0.1 wordpress
127.0.0.1 project1.wordpress
127.0.0.1 project2.wordpress
# save and exit. the command to do this is:
:wq!
###Step 2: EDIT APACHE CONFIG FILE
Press cmd + shift + g
and paste this: /Applications/MAMP/conf/apache/
open the file "httpd.conf" with your favorite text editor.
In that file, search for # NameVirtualHost *
and replace it with this one:
NameVirtualHost *
<virtualHost *>
ServerName example.com
ServerAlias example.com *.example.com
DocumentRoot "/Applications/MAMP/htdocs/"
<directory "/Applications/MAMP/htdocs/">
Options Indexes FollowSymLinks Includes
AllowOverride All
Order allow,deny
Allow from all
</directory>
</virtualHost>
if it doesn't exists, add it underneath <VirtualHost> definition
.
###Step 3: ENABLING WORDPRESS MULTISITE
Follow the official instructions from Wordpress Codex
If all goes well and you are able to login to your site's
Dashboard, good job! however if you get the usual bug where
when you login, you only get redirected to the same page,
don't panic, take a deep breath and add this to your 'wp-config.php'
to the line before the comment:
/* That's all, stop editing! Happy blogging. */
define('ADMIN_COOKIE_PATH', '/');
define('COOKIE_DOMAIN', '');
define('COOKIEPATH', '');
define('SITECOOKIEPATH', '');
hit save, and try logging in again. :)